Now its time to keep your new seedlings alive. If you purchased your seedlings from a reputable greenhouse, they should have done all of this step for you. They should have also hardened them off from the sun and wind. They should be ready to plant. If that is the case, you can skip this step(I still recommend reading it).
Pepper and tomato seedlings can be tricky to keep alive, because they are so fragile. They need light, but too much can burn them. They need food, but too much can kill them. They need humidity, but too much will cause them to get sick. If they make it through all of this, they still need to be hardened off from the sun and wind before they can be planted outside.
Lets start with lighting. If you are using florescent lights make sure not to place them too close to the seedlings, or they will get sunburnt. Its hard to give specifics, because some lights are stronger than others. Just make sure that they are at least a foot away from your plants. If you start too far, you can always put them closer to the light. If your seedlings are outside, then you will want to shade them from getting full sun. We use 30% shade cloth, and double it to 60% for the first week. Once they start growing new leaves, we remove a layer of the cloth. This is in a greenhouse. Bottom line… less is more.
Next we should talk about food. Seedlings do not need food for a few weeks after sprouting. Once feeding starts, we use a complete plant food. Complete plant foods not only have N-P-K, they also have all the nutrients that the plant needs. We then measure it to to an EC of .5 (200-350 PPM). We make sure that the PH is between 5.5 and 6.5. We try to target between 5.8, and 6.0. As the seedlings grow we slowly increase the EC never exceeding .75. In an upcoming chapter we go much further into detail on feeding. We will explain what all of that means.
So how often do you feed the seedlings? When using soil we alternate between food and water. Meaning that we use our nutrient solution, then the next time we only give the plant water. When we give water, we give enough so that it flushes any extra food out of the soil. If we are using coco or rockwool, we always just feed, but sometimes we flush with water first, then feed.
If temperatures get too cold, the seedlings can catch a kind of sickness. They can also get sick if they get too humid or wet. For this reason we always use a fan to keep air circulating the plants.
Once the plant is almost large enough to plant outside, it is time to harden them off. What that means is that you will slowly acclimate the seedlings to be able to receive full sun without burning, and full wind without breaking. If you had a fan on your seedlings and a strong light, then this process should go smooth. When preparing to plant outside we first make sure to shelter the plants from the wind. We only put the plant outside for one hour. The second day we increase the time to two hours, and we remove some of the shelter to let the plants get more wind exposure. Every day the time outside increases until we feel confident the plant wont die.
We always plant in the evening so that the plant is out of the sun and has time to acclimate to it’s new environment and when the following days are forecast to be cloudy. In a greenhouse this is where we use layers of shade cloth. We remove them as necessary to keep the plants alive.